Its hard to mention as the overall experience was soo good! I would say it was little stinky in the room (doesnt really bother) and maybe little bit complicated with commuting to the center, buses can bring you anywhere but it can take a while (bike is a solution :) Besides, Leblon is little bit high end area, so prices might be little higher than average Rio. For me this was not really Any issue.
Staff is exceptionally friendly, helpful, hospitable and in general nice, interesting people, very enthusiastic about their job and they treat guests not just like customers.
The location of the hostel is amazing: literally 1 min walk to (the best in Rio city!) beach of Leblon. It's the most safe, clean and quite location in my opinion. Ipanema and Copa beaches are quite crowded and noisy, I preferred hanging at Leblon.
Z.bra offers beach umbrellas and sunbeds for free, so you don't need to buy/organize anything for visiting seaside. Bike rental is a huge benefit, I strongly recommend everyone to use it, Rio is a lot more enjoyable with a bike: cycle along the shore (cycling tracks are all around the city and stretch across all beaches starting from leblon), and doing a tour around Lagoa (visiting Parc Lage is a must!) is a great experience!
The rooms and beds are pretty good, I stayed in dozen of hostels around the world, and Z.bra has a Nice concept. The best thing is that you have personal locker and power Socket right in your bed case and in the room with more storage, so no worries about safety of your stuff. Bedsheets are incl and you can also rent a towel at almost no price. Air conditioning Works good, so its never hot and always Nice to stay chilly indoor while its burning in the street. Breakfasts were also good (cereals, fruits, toasts, desertes, all you might need for morning basically).
Thanks to Z.bra staff and guests, i had great fun :) highly recommended!